Nicotinic Receptor Binding Site Probed with Unnatural Amino Acid Incorporation in Intact Cells

• Published in: Science (American Association for the Advancement of Science) Vol. 268; no. 5209; pp. 439 - 442
• Main Authors: Nowak, Mark W., Kearney, Patrick C., Sampson, Jeffrey R., Saks, Margaret E., Labarca, Cesar G., Silverman, Scott K., Zhong, Wenge, Thorson, Jon, Abelson, John N., Davidson, Norman, Schultz, Peter G., Dougherty, Dennis A., Lester, Henry A.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 21-04-1995; American Association for the Advancement of Science; The American Association for the Advancement of Science
• Subjects: Agonists; Amino acids; Animals; Base Sequence; Binding Sites; Biological and medical sciences; Cell receptors; Cell structures and functions; Cellular biology; Cholinergic receptors; Codon; Dose response relationship; Feedback (Response); Fundamental and applied biological sciences. Psychology; Hydrogen Bonding; Ligands; Membranes; Messenger RNA; Molecular and cellular biology; Molecular Sequence Data; Monoamines receptors (catecholamine, serotonine, histamine, acetylcholine); Mutagenesis; Mutagenesis, Site-Directed; Nicotinic receptors; Nonsense; Oocytes; Phenylalanine - analogs & derivatives; Phenylalanine - chemistry; Proteins; Receptors; Receptors, Nicotinic - chemistry; Receptors, Nicotinic - metabolism; Structure-Activity Relationship; Transfer RNA; Translation; Tyrosine - analogs & derivatives; Tyrosine - chemistry; Xenopus; Synthetic product; Nonsense mutation; Aminoacid; Alpha-Peptide chain; Binding site; Structure function relationship; Nicotinic receptor
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.7716551

The nonsense codon suppression method for unnatural amino acid incorporation has been applied to intact cells and combined with electrophysiological analysis to probe structure-function relations in the nicotinic acetylcholine receptor. Functional receptors were expressed in Xenopus oocytes when tyrosine and phenylalanine derivatives were incorporated at positions 93, 190, and 198 in the binding site of the α subunit. Subtle changes in the structure of an individual side chain produced readily detectable changes in the function of this large channel protein. At each position, distinct features of side chain structure dominated the dose-response relation, probably by governing the agonist-receptor binding.